Metabolomics Changes of Serum and Tissues in Mice Died of Acute Tetracaine Poisoning / 法医学杂志

Objective To study the changes of metabolites in serum and tissues （kidney, liver and heart） of mice died of acute tetracaine poisoning by metabolomics, to search for potential biomarkers and related metabolic pathways, and to provide new ideas for the identification of cause of death and research on toxicological mechanism of acute tetracaine poisoning. Methods Forty ICR mice were randomly divided into control group and acute tetracaine poisoning death group. The model of death from acute poisoning was established by intraperitoneal injection of tetracaine, and the metabolic profile of serum and tissues of mice was obtained by ultra-high performance liquid chromatography-electrostatic field orbitrap high resolution mass spectrometry （UPLC-Orbitrap HRMS）. Multivariate statistical principal component analysis （PCA） and orthogonal partial least square-discriminant analysis （OPLS-DA） were used, combined with t-test and fold change to identify the differential metabolites associated with death from acute tetracaine poisoning. Results Compared with the control group, the metabolic profiles of serum and tissues in the mice from acute tetracaine poisoning death group were significantly different. Eleven differential metabolites were identified in serum, including xanthine, spermine, 3-hydroxybutylamine, etc.; twenty-five differential metabolites were identified in liver, including adenylate, adenosine, citric acid, etc.; twelve differential metabolites were identified in heart, including hypoxanthine, guanine, guanosine, etc; four differential metabolites were identified in kidney, including taurochenodeoxycholic acid, 11, 12-epoxyeicosatrienoic acid, dimethylethanolamine and indole. Acute tetracaine poisoning mainly affected purine metabolism, tricarboxylic acid cycle, as well as metabolism of alanine, aspartic acid and glutamic acid. Conclusion The differential metabolites in serum and tissues of mice died of acute tetracaine poisoning are expected to be candidate biomarkers for this cause of death. The results can provide research basis for the mechanism and identification of acute tetracaine poisoning.

Optimization of Preparation Technology of Tetracaine Hydrochloride Ethosomes / 中国药房

OBJECTIVE： To establish a method for determining the content of tetracaine hydrochloride （TCH） ethosomes， and to optimize the preparation technology. METHODS： The content of TCH was determined by HPLC. TCH ethosomes were prepared with injection-ultrasonic method. Using drug-loading amount， egg lecithin concentration and ethanol volume fraction as factor， encapsulation efficiency as index， central composite design-response surface methodology was used to optimize the prescription based on the single factor test. The prepared ethosomes were characterized and the stability was evaluated. RESULTS： The linear range of TCH was 10-100 μg/mL （r＝0.999 5）； the limit of quantification was 0.045 μg/mL， and detection limit was 0.021 μg/mL. RSD of precision， stability and repeatability tests were less than 2％. The recoveries ranged 97.80％-103.20％ （RSD＝0.36％， n＝9）. The optimal preparation technology included that the adding amount of TCH control was 1 mg； the concentration of egg lecithin was 7 mg/mL， and ethanol volume fraction was 33％. Under this technology， the average encapsulation efficiency was 64.50％ （n＝3）， the relative error of which from the predicted value （64.92％） was 0.64％. TCH ethosome was a clear blue liquid with a blue opalescence. Its appearance was spherical， its shape was round， smooth， uniform in size； the average particle size was （80.33±2.24） nm， and the average Zeta potential was （－22.6±1.33） mV. TCH ethosome was stable during 10 days under 4 ℃， sealed and protected from light. CONCLUSIONS： The optimal preparation process is stable and feasible. Established method is simple and rapid.

Assessment of non-invasive tear break-up time and tear meniscus height after instillation of three different formulations of anesthetic eye drops by Oculus Keratograph 5M / Avaliação do tempo de ruptura lacrimal não invasivo e da altura do menisco lacrimal após a instilação de três diferentes formulações de colírio anestésico por Oculus Keratograph 5M

Abstract Purpose: To assess the non-invasive tear break-up time (NITBUT) and tear meniscus height (TMH) after instilling the three different types of anesthetic eye drops by Oculus Keratograph 5M. Methods: In this prospective study, 85 healthy subjects (85 eyes) were randomly divided into three groups. The groups were randomly received lidocaine hydrochloride 2%, proparacaine hydrochloride 0.5%, and tetracaine hydrochloride 0.5%. The qualitative and quantitative parameters of tear film were assessed using NITBUT and TMH, respectively. In all groups, the quantity of tear film using TMH was measured in the right eye of subjects, while the quality of tear film using NITBUT was assessed in the left eye. The analysis of variance (ANOVA) was used to compare the difference between before and after the intervention. A P-value < 0.05 was considered significant. Results: Differences for TMH and NITBUT between before and after applying lidocaine hydrochloride 2% were not statistically significant (P > 0.05). The mean values of NITBUT and TMH after the instillation of proparacaine hydrochloride 0.5% showed a significant decrease than before the intervention (P < 0.05). Also, after the use of tetracaine hydrochloride 0.5%, the mean value of NITBUT was significantly increased (P < 0.05), but the mean value of TMH was significantly decreased than before the intervention (P < 0.05). Conclusion: Our study showed that lidocaine hydrochloride 2% as an anesthetic eye drops can be an appropriate choice for eye examinations due to a lack of significant effect on the quantity and quality of tear film.

Resumo Objetivo: Avaliar o tempo de ruptura lacrimal não invasivo (NITBUT) e a altura do menisco lacrimal (TMH) após instilar os três tipos diferentes de colírio anestésico pelo Oculus Keratograph 5M. Métodos: Neste estudo prospectivo, 85 indivíduos saudáveis (85 olhos) foram divididos aleatoriamente em três grupos. Os grupos receberam aleatoriamente cloridrato de lidocaína a 2%, cloridrato de proparacaína a 0.5% e cloridrato de tetracaína a 0.5%. Os parâmetros qualitativos e quantitativos do filme lacrimal foram avaliados utilizando NITBUT e TMH, respectivamente. Em todos os grupos, a quantidade de filme lacrimal utilizando TMH foi medida no olho direito dos sujeitos, enquanto a qualidade do filme lacrimal usando NITBUT foi avaliada no olho esquerdo. A análise de variância (ANOVA) foi utilizada para comparar a diferença entre antes e depois da intervenção. Um valor de P < 0.05 foi considerado significativo. Resultados: Diferenças para TMH e NITBUT entre antes e depois da aplicação de cloridrato de lidocaína a 2% não foram estatisticamente significantes (P > 0.05). Os valores médios de NITBUT e TMH após a instilação de cloridrato de proparacaína a 0.5% mostraram uma diminuição significativa do que antes da intervenção (P < 0.05). Além disso, após o uso de cloridrato de tetracaína a 0.5%, o valor médio de NITBUT foi significativamente aumentado (P < 0.05), mas o valor médio de TMH foi significativamente menor do que antes da intervenção (P < 0.05). Conclusão: Nosso estudo mostrou que o cloridrato de lidocaína a 2% como colírio anestésico pode ser uma escolha apropriada para exames oftalmológicos devido à falta de efeito significativo sobre a quantidade e a qualidade do filme lacrimal.

Application of Local Anesthesia With Lidocaine Carbonate and Tetracaine in Nasal Endoscopic Surgery / 中国微创外科杂志

Objective To investigate the application value of local anesthesia with lidocaine carbonate and tetracaine in the prevention of tracheal intubation and extubation response in nasal endoscopy. Methods From January 2016 to March 2017, 90 patients scheduled for endoscopic sinus surgery were randomly divided into 3 groups,with 30 cases in each group.Before endotracheal intubation,1%tetracaine was used for endotracheal surface anesthesia,and air was filled into tracheal intubation airbag(group T). The intratracheal surface was sprayed with physiological saline and 1.73%lidocaine carbonate was filled into tracheal intubation airbag (group C).The 1%tetracaine was used for endotracheal surface anesthesia,and 1.73%lidocaine carbonate was filled into tracheal intubation airbag(group TC).The mean artery pressure(MAP)and heart race(HR)were recorded before induction(T1), immediately after intubation(T2),immediately after extubation(T3),and 5 min after extubation(T4).The scoring of cough during extubation was recorded.Sore throat scores were recorded by using Visual Analogue Scale(VAS)at 30 min,1 h,2 h,6 h and 24 h after extubation,respectively. Results The MAP and HR were less in the group T and TC than those in the group C at T 2(F=8.384,P=0.000;F=6.154,P=0.003), less in the group C and TC than in the group T at T 3(F=14.112, P=0.000; F=3.514,P=0.034).The cough scores were the lowest in the group TC(0.9 ±0.7), median in the group C(1.3 ±0.7), and the highest in the group T(1.7 ±0.5)(F=10.307, P=0.000).The VAS scores of pharyngalgia were the lowest in the group TC (2.1 ±0.8),median in the group C(3.0 ±1.2),and the highest in the group T(3.8 ±1.3)(F=17.961,P=0.000)at 30 min after surgery,and lower in the group TC(1.8 ±0.7)than in the group T(2.5 ±1.0)(F=5.058,P=0.008)at 1 h after surgery.Conclusion Local anesthesia combined with lidocaine carbonate and tetracaine can effectively reduce the cardiovascular response of endotracheal intubation and extubation and relieve the incidence of postoperative cough and sore throat.

The comparative study of lidocaine and tetracaine urethral surface anesthesia in catheter related bladder discomfort of male patients after thoracoscopy surgery / 实用医学杂志

Objective To compare the effects of tetracaine or lidocaine anesthesia effect on urethral agita-tion in thoracoscopic male patients during recovery period. Method One hundred and twenty male adults(18 ~60 yr),ASA physical status I and II undergoing elective thoracoscopic surgery ,were randomly divided into three groups of 30 cases in each one. The control group received paraffin oil lubrication catheterization after general anes-thesia induction,whereas the experimental groups received tetracaine gel or lidocaine gel 3~5 g in urethral surface anesthesia before catheterization. Intra-operatively ,urinary catherization was performed with a 16 Fr Foley′s cathe-ter,and a balloon was inflated with 10 mL distilled water. The CRBD was assessed at 0,1,and 12 h after patient′s arrival in the post-anaesthesia care unit. Severity of CRBD was graded as none,mild,moderate and severe. Data were analysed by one-way ANOVA and Fisher′s exact test. P < 0.05 was considered significant. Results Inci-dence and severity of CRBD was reduced in the experimental groups compared with the control group(P < 0.05). Postoperative pain as assessed by visual analogue scale and Richer-SAS was also reduced in the experimental group compared with the control group. Furthermore,in the tetracaine group,catheter-related complaint had less discom-fort than that in the lidocaine group. Conclusion Lidocaine and tetracaine surface anesthesia can significantly reduce catheter-related bladder discomfort after induction ,and tetracaine mucilage lasts for a longer time and less discomfort.

Determination of heavy metals Pb,Cd,Sb in tetracaine hydrochloride injection by atomic absorption spectrometry-graphite furnace / 中国生化药物杂志

Objective To establish an external calibration method of atomic absorption spectrometry-graphite furnace for determination of heavy metals Pb,Cd,Sb in tetracaine hydrochloride injection.Methods Microwave digestion for the pretreatment method was used,three kinds of heavy metal elements were determined by graphite atomic absorption spectrometry-graphite furnace Results The linear ranges of Pb,Cd,Sb were 0-80.0 ng/mL,0-2.0 ng/mL,0-40.0 ng/mL,therecovies were 92.7%-105.7%,95.8%-103.4%,92.1%-103.5%,respetively.The relative standard deviationless than 6.0%(n=9).Conclusion The method is simple and accurate,which can be used for the control of Pb,Cd,Sb in tetracaine hydrochloride injection.

EFFICACY OF TOPICAL APPLICATION OF EPHEDRINE AND FURACILIN NASAL DROPS COMBINED WITH TETRACAINE IN REDUCING COMPLICATIONS OF POSTOPERATIVE NASAL PACK REMOVAL / 现代医院

Objective To assess the efficacy of topical application of Ephedrine and furacilin nasal drops combined with tetracaine in reducing complications of pack removal after nasal surgery.Methods 81caseshaving un-dergone nasal septum surgery were randomly divided into the experimental group and control group: the former were treated with Ephedrine and furacilin nasal drops combined with tetracaine and the blank control group.The occur-rence of complications at removing nasal fillers after nasal surgery was assessed.Results The hemorrhage and pain in the experimental group were significantly less than those in the blank control group (p <0.05).Conclusion top-ical application of Ephedrine and furacilin nasal drops combined with tetracaineis an effective method for reducing the pains of pack removal after nasal surgery.

The effect of tetracaine jelly on hemodynamics during extubation period in general anesthesia / 中国医师进修杂志

Objective To study the effect of tetracaine jelly on hemodynamics during extubation period in general anesthesia.Methods One hundred patients who performed tracheal cannula and general anesthesia were divided into control group (50 patients) and experiment group (50 patients) by random digits table method.Control group:sterile paraffin oil was applied to the endotracheal tube.Experiment group:tetracaine jelly was applied to the endotracheal tube.The systolic blood pressure (SBP),diastolic blood pressure (DBP) and heart rate(HR) were measured before the anesthesia induction(T1),5 min after stopping infusion drugs (T2),1 min after tracheal extubation (T3),3 min after tracheal extubation (T4) and 5 min after tracheal extubation (T5) were observed.The resistant effect after waking and the number of sore throat,hoarseness were recorded.Results The level of SBP,DBP,HR at T1 and T2 had no significant difference between two groups (P ＞ 0.05).The level of SBP,DBP,HR at T3-T5 in experiment group were significantly lower than those in control group [SBP:(122.3 ± 11.3),(120.0 ± 9.8),(112.0 ± 6.3) mmHg (1 mmHg =0.133 kPa) vs.(158.3 ± 15.0),(142.5 ± 13.5),(133.0± 14.5) mmHg;DBP:(75.0 ± 13.5),(75.8 ± 10.5),(58.3 ±4.2) mmHg vs.(111.0 ± 20.3),(106.5 ± 12.8),(63.8 ± 15.8) mmHg;HR:(81.9 ± 13.7),(83.6 ± 13.4),(60.7 ± 3.5) times/min vs.(113.5 ± 19.4),(117.5 ± 21.7),(71.8 ± 14.6) times/min](P ＜ 0.05).The total effective rate of tolerance in experiment group was higher than that in control group [96％(48/50) vs.56％(28/50)],the rate of sore throat and hoarseness were lower than those in control group [6％ (3/50) vs.48％ (24/50),4％ (2/50) vs.36％ (18/50)],there were significant differences (P ＜ 0.05).Conclusion Tetracaine jelly can reduce the cardiovascular response of tracheal extubation,enhance the tolerance of tracheal tube and decrease the morbidity of sore throat and hoarseness.

Estudo clínico e histológico das pálpebras e conjuntiva hígidas submetidas ao tratamento tópico com soluções anestésicas em coelhos / Clinical and histological evaluation of healthy eyelid and conjunctiva subject to local treatment with anesthetic solutions in rabbits

Avaliaram-se as apresentações comerciais de colírios anestésicos aplicados em 63 coelhos da raça Nova Zelândia, distribuídos em três grupos (G1, G2 e G3) de 21 animais cada e que receberam instilação de uma gota em cada olho seis vezes ao dia. Os animais do G1 foram tratados com colírio de cloridrato de proparacaína a 0,5%; os do G2, com colírio de cloridrato de tetracaína a 1% associado à fenilefrina a 0,1%; e os do G3, com solução fisiológica. Cada grupo foi subdividido em três subgrupos com sete animais cada, os quais foram tratados por três, sete e 15 dias. No final de cada tratamento, dois animais de cada subgrupo foram sacrificados para exame histológico de fragmentos retirados da conjuntiva, da terceira pálpebra e das pálpebras. Observou-se, ao exame clínico, episclerite em graus diversos em 100% dos animais do G1, no terceiro, sétimo e 15º dia, e em apenas 17,8% nos do G2, nestes mesmos dias. Ao exame microscópico, observaram-se aumento do número de células califormes, proliferação de folículos linfoides, aumento do número de eosinófilos e aumento do espaço intersticial nas pálpebras dos animais do G1. Pôde-se concluir que o colírio de tetracaína a 1% associado à fenilefrina a 0,1% promoveu maior toxicidade à conjuntiva ocular e às pálpebras de coelhos quando comparado ao colírio de proparacaína a 0,5%.

This work aimed to evaluate commercial presentations of anesthetic eye drops in sixty three New Zealand rabbits which were separated equally in three groups (G1, G2 and G3). The G1 group was treated with 0.5% proparacaine chloridrate eye drop, G2 group with 1% tetracaine chloridrate associated with 0.1% phenylephrine eye drop and G3 group with 0.9% physiologic solution eye drop. All of them received one drop in each eye six times a day. Each group was subdivided into three subgroups (seven rabbits), which are treated for 3, 7 and 15 days. At the end of each treatment, two animals in each subgroup were subject to euthanasia, for the purpose of conjunctiva, eyelids and third eyelids histological evaluation. At the clinical exam, different grades of episcleritis were found in all rabbits in G2 group and only in 17.8% of the rabbits in G1 group. Eye and eyelid histologic evaluation of G2 group revealed an upgrade of goblet cells and eosinophil number, lymphoid follicle proliferation and increase of interstitial space in the eyelids. We could conclude that 1% tetracaine associated with 0.1% phenylephrine eye drop caused more eyelid and ocular conjunctiva toxicity than 0.5% proparacaine eye drop.

Neurotoxic effects of different concentrations of tetracaine and ropivacaine on brachial plexus nerve in rats / 中华麻醉学杂志

Objective To investigate the neurotoxic effects of different concentrations of tetracaine and ropivacaine on the brachial plexus nerve in rats.Methods Forty-eight male Sprague-Dawley rats,weighing 410-430 g,were randomly divided into 8 groups (n =6 each):normal saline group (group NS),0.25％,0.50％ and 1.00％ tetracaine groups (groups T1-3 ),and 0.25％,0.50％,1.00％ and 2.00％ ropivacaine groups (groups R1-4 ).The rats received injection of normal saline 1.0 ml,0.25％,0.50％ and 1.00％ tetracaine 0.5 ml,0.25％,0.50％,and 1.00％ ropivacaine 1.0 ml and 2.00％ ropivacaine 0.5 ml in groups NS,T1-3 and R1-4 respectively through one side of the axillary sheath.The other side of the axillary sheath served as control side.Five days later,compound action potential and nerve conduction velocity (NCV) of the brachial plexus nerve were measured.Tne brachial plexus nerve was obtained as the specimen for microscopic examination with light and transmission electron microscope.Results Compared with the control side and group NS,the compound action potential and NCV of the brachial plexus nerve were significantly decreased in groups T2,3 and R3,4 ( P ＜ 0.05 ).The compound action potential and NCV of the brachial plexus nerve were gradually decreased with the increasing concentrations of tetracaine in groups T1 3 ( P ＜ 0.05 ).The compound action potential and NCV of the brachial plexus nerve were significantly decreased in group R4 as compared with groups R1-3 (P ＜ 0.05).The microscopic examination showed that the pathologic changes were more severe in groups T2,3 and R3,4 than those on the control side and than in group NS.Conclusion 0.50％ and 1.00％ tetracaine,and 1.00％ and 2.00％ ropivacaine can result in pathologic damage to the brachial plexus nerve in rats and the degree of damage is related to the concentration.

Efficacy and safety of a lidocaine/tetracaine medicated patch or peel for dermatologic procedures: a meta-analysis / 대한마취과학회지

BACKGROUND: To justify the use of the lidocaine/tetracaine medicated patch or peel as a preventive treatment for reducing pain and discomfort in adults and children. We reviewed randomized controlled trials (RCTs) to evaluate the efficacy and safety of the lidocaine/tetracaine medicated patch or peel compared with placebo. METHODS: Ten RCTs (574 patients) were included in this systemic review. Relevant studies were identified through searches of MEDLINE, SCOPUS and the Cochrane database library. The outcome was the adequacy of cutaneous anesthesia reflected in the patient's assessment of pain intensity during minor dermatologic procedures and adverse effects after application of the lidocaine/tetracaine medicated patch or peel versus placebo. RESULTS: The efficacy of the lidocaine/tetracaine patch or peel was consistently very significantly beneficial 30 or 60 minutes after the application compared to placebo (Relative risk, RR: 2.5; Number needed to treat, NNT: 2.2). We did not identify any difference in the effectiveness of adequate analgesia between the lidocaine/tetracaine patch and peel (the number needed to treat or to harm, NNT 2.4 vs. 2.0). No serious side effects or adverse events were observed with the lidocaine/tetracaine medicated patch or peel and placebo. Minor skin reactions were transient and resolved without treatment (Odd ratio, OR: 1.4 and 95% confidence interval, CI: 0.9-2.1; NNT: 14.9). CONCLUSIONS: The lidocaine/tetracaine medicated patch or peel is a well accepted, effective and safe method for minor dermatologic procedures based on pooled data of trials in terms of adequacy of cutaneous anesthesia and adverse effects.

Anestésicos tópicos / Topical Anesthetics

Introdução: Os anestésicos tópicos, de indiscutível utilidade na rotina do dermatologista, têm sido cada vez mais utilizados pela população, nem sempre com prescrição e supervisão médica. Seu uso pode envolver complicações ligadas, principalmente, à aplicação inadequada, seja em pele lesada ou inflamada, em grandes áreas corporais, em mucosas ou em pacientes de risco. As reações adversas podem variar desde efeitos locais transitórios, reações alérgicas e/ou irritativas, até quadros mais graves, embora raros, como metemoglobinemia, arritmias e insuficiência cardiorrespiratória. Este artigo visa discutir as preparações comerciais de anestésicos tópicos hoje disponíveis, seu histórico, farmacologia, aplicação clínica e complicações.

Introduction: The use of topical anesthetics, has increased in recent years.While they are undoubtedly useful when recommended appropriately by a dermatologist, the improper use of topical anesthetics may result in complications, mainly due to inadequately applying them to wounded or inflamed skin; use on large areas of the body or mucus membranes; or use by high-risk patients. Adverse reactions can include transient local effects, allergic and/or irritative reactions, or more severe (though rare) effects, such as methemoglobinemia, arrhythmias, and cardiorespiratory failure. This paper discusses the commercial formulations of topical anesthetics currently available, their history, pharmacology, clinical use, and potential side effects.

The Effect of Tetracaine.HCl on Rotational Mobility of n-(9-Anthroyloxy) Stearic Acid in Outer Monolayers of Neuronal and Model Membranes

To provide a basis for studying the pharmacological actions of tetracaine.HCl, we analyzed the membrane activities of this local anesthetic. The n-(9-anthroyloxy) stearic and palmitic acid (n-AS) probes (n = 2, 6, 9, 12 and 16) have been used previously to examine fluorescence polarization gradients. These probes can report the environment at a graded series of depths from the surface to the center of the membrane bilayer structure. In a dose-dependent manner, tetracaine.HCl decreased the anisotropies of 6-AS, 9-AS, 12-AS and 16-AP in the hydrocarbon interior of synaptosomal plasma membrane vesicles isolated from bovine cerebral cortex (SPMV), and liposomes derived from total lipids (SPMVTL) and phospholipids (SPMVPL) extracted from the SPMV. However, this compound increased the anisotropy of 2-AS at the membrane interface. The magnitude of the membrane rotational mobility reflects the carbon atom numbers of the phospholipids comprising SPMV, SPMVTL and SPMVPL and was in the order of the 16, 12, 9, 6, and 2 positions of the aliphatic chains. The sensitivity of the effects of tetracaine.HCl on the rotational mobility of the hydrocarbon interior or surface region was dependent on the carbon atom numbers in the descending order 16-AP, 12-AS, 9-AS, 6-AS and 2-AS and on whether neuronal or model membranes were involved in the descending order SPMV, SPMVPL and SPMVTL.

Spinal Anesthesia with Isobaric Tetracaine in Patients with Previous Lumbar Spinal Surgery

PURPOSE: Previous lumbar spinal surgery (PLSS) is not currently considered as a contraindication for regional anesthesia. However, there are still problems that make spinal anesthesia more difficult with a possibility of worsening the patient's back pain. Spinal anesthesia using combined spinal-epidural anesthesia (CSEA) in elderly patients with or without PLSS was investigated and the anesthetic characteristics, success rates, and possible complications were evaluated. MATERIALS AND METHODS: Fifty patients without PLSS (Control group) and 45 patients with PLSS (PLSS group) who were scheduled for total knee arthroplasty were studied prospectively. A CSEA was performed with patients in the left lateral position, and 10 mg of 0.5% isobaric tetracaine was injected through a 27 G spinal needle. An epidural catheter was then inserted for patient controlled analgesia. Successful spinal anesthesia was defined as adequate sensory block level more than T12. The number of skin punctures and the onset time were recorded, and maximal sensory block level (MSBL), time to 2-segment regression, success rate and complications were observed. RESULTS: The success rate of CSEA in Control group and PLSS group was 98.0%, and 93.3%, respectively. The median MSBL in PLSS group was higher than Control group [T4 (T2-L1) vs. T6 (T3-T12)] (p < 0.001). There was a significant difference in the number of patients who required ephedrine for the treatment of hypotension in PLSS group (p = 0.028). CONCLUSION: The success rate of CSEA in patients with PLSS was 93.3%, and patients experienced no significant neurological complications. The MSBL can be higher in PLSS group than Control group.

Determination of the Entrapment Efficiency of Tetracaine Hydrochloride Liposome by the Microcolumn Centrifugation-HPLC / 中国药房

OBJECTIVE:To develop a method for determining the entrapment efficiency of tetracaine hydrochloride liposome.METHODS:The microcolumn centrifugation was adopted to separate the free tetracaine hydrochloride from liposomes;the content of tetracaine hydrochloride was determined by HPLC and the entrapment efficiency was computed.RESULTS:By microcolumn centrifugation,the liposomes and the free tetracaine hydrochloride were well-separated.The recovery rate of the blank liposomes was 90.4%～100.1%;the absorption rate of free tetracaine hydrochloride was 96.6%～99.2%;and the entrapment efficiencies of tetracaine liposomes stood at about 80%.CONCLUSION:This method established for determining the entrapment efficiency of tetracaine hydrochloride liposome is simple,rapid and reproducible.

Preparation and Quality Control of Qindiyou Emulsion / 中国药房

OBJECTIVE:To prepare qingdiyou emulsion and to establish its quality control.METHODS:Qindiyou emulsion was prepared by emulsification by using tetracaine hydrochloride as principal agent.The content of tetracaine hydrochloride was determined by UV spectrophotometry.The stability of 3 batches of samples was investigated.RESULTS:The preparation was white emulsion.The linear range of tetracaine hydrochloride was 3.168～9.504 ?g?mL-1(r=0.999 9),with an average recovery rate of 99.68%(RSD=0.49%).The 3 batches of sample preparations were proved to be stable in quality.CONCLUSION:This method is simple in operation,accurate in content determination,and stable and controllable in quality within expiration date.

Spinal Anesthesia with 0.2% Hypobaric Tetracaine for Total Hip Replacement / 대한마취과학회지

BACKGROUND: Using hypobaric local anesthetics, patients undergoing total hip replacement surgery (THR) can be anesthetized in the lateral decubitus position with operative side up, and do not need to be repositioned for operation. This can save preparation time and inadvertent change of anesthetic level due to position change. Number of studies have examined the use of hypobaric local anesthetics for THR, but the main focus of the studies was to compare the effect of various drugs or baricities, rather than adequate dosages. Therefore, we aimed to determine adequate dosages of hypobaric tetracaine for THR. METHODS: Sixty patients were randomly allocated into three groups. Spinal anesthesia was performed in the lateral decubitus position with the operated side uppermost using 0.2% tetracaine diluted with distilled water, 10, 12, or 14 mg was administered into the subarachnoid space. RESULTS: Time to T10 block, the level of maximal sensory and motor block, and the incidence of hypotension were no different in the three dosage groups. The number of patients who showed adequate anesthesia (more than T10 and modified Bromage scale 2) were no different. Duration of sensory block and the time to complete motor recovery increased with dosage. The number of patients with less than a 2 hour sensory block was higher in the 10 mg group (50%) than in the two other groups (10% in 12 microgram, 0% in 14 microgram). CONCLUSIONS: 10 mg of hyperbaric tetracaine was not enough, and 14 mg adequate for a hip surgery of 2 hour duration. The two doses were similar in terms of the sensory and motor block level and the incidence of hypotension.

Enhancement of ethanol on percutaneous permeation and topical anaesthesia of tetracaine gel / 中国临床药理学与治疗学

AIM: To investigate the enhancement of ethanol on percutaneous permeation and topical anaesthesia of tetracaine gel. METHODS: Tetracaine (4%, w/w) gels were prepared by using 20% and 70% ethanol as penetration enhancers. Franz diffusion chamber and UV spectrophotometry were adopted in the transdermal osmotic test of isolated mouse skin. Von Frey test was used to evaluate the topical anesthetic effect of tetracaine gels. RESULTS: 20% and 70% ethanol greatly improved the percutaneous permeation of tetracaine gel (P

The Evaluation of Topical Anesthetic Effects of a Liposome Encapsulated Mixture of Local Anesthetics (Lipo-MLA) / 대한마취과학회지

BACKGROUND: This study investigated the effect of topical analgesic effects of a liposome encapsulated mixture of local anesthetics (lipo-MLA) compared with EMLA. METHODS: 3% lipo-MLA (0.5% tetracaine base, 2.5% lidocaine base) and 5% lipo-MLA (1% tetracaine base, 4% lidocaine base) were encapsulated into liposomal vesicles made with egg yolk phosphatidylcholine, cholesterol and phosphatidyldioleoyl. 3% lipo-MLA and EMLA were applied to volunteers' forearms bilaterally with and without an occlusive dressing. The topical anesthetic effects of the lipo-MLA and EMLA as a control were evaluated by the pinprick test in 28 adult volunteers after 60 minutes of application. The analgesic influence of the concentration of local anesthetics was also compared with 3% and 5% lipo-MLA under a non-occlusive dressing. RESULTS: Analgesic effects of the 3% lipo-MLA were similar with EMLA under an occlusive dressing for 60 minutes. In addition, analgesic effects of the 3% lipo-MLA under a non-occlusive dressing were more potent than EMLA. Lipo-MLA under a non-occlusive dressing showed more potent analgesic effect than lipo-MLA under an occlusive dressing. 5% lipo-MLA was more potent than 3% lipo-MLA under a non-occlusive dressing. CONCLUSIONS: Lipo-MLA has more potent analgesic effects than EMLA without an occlusive dressing and 5% lipo-MLA is more potent than 3% lipo-MLA. Therefore, lipo-MLA appeared to be an improved topical analgesic formulation which provides a more potent and convenient topical application.

The Effect of the Injected Volume on the Spread of Spinal Anesthesia with Hypobaric Tetracaine / 대한마취과학회지

BACKGROUND: The properties of hypobaric spinal anesthesia are excellent in sensory and motor block with low concentration solutions, increased venous return, and hemodynamic stability. Much volume is needed with hypobaric spinal anesthesia because low concentration solutions are used. The purpose of this study was to examine the effects of the injected volume on the level of anesthesia in hypobaric spinal anesthesia during a total hip replacement. METHODS: Twenty-seven adult patients scheduled for a total hip replacement were assigned randomly to two groups, one with 0.1% (n = 14), and the other with 0.2% (n = 13) hypobaric tetracaine spinal anesthesia. 8 mg of tetracaine was used for male patients and 7 mg for female patients. Hence the injected volumes were 8 ml for male and 7 ml for female patients in 0.1% solution and 4 ml for male and 3.5 ml for female patients in 0.2% solution, respectively. Epinephrine was mixed to either solution in concentrations of 1:200,000. The speed of injection was fixed at the rate of 0.2 ml/sec. RESULTS: The height of sensory block with the 0.1% was one dermatome higher (T5.7) than with the 0.2% tetracaine solution (T6.7). The time for sensory block (11.4 min vs 12.3 min) and the time for motor block (10.0 min vs 15.0 min) with 0.1% was shorter than that with the 0.2% tetracaine solution. The duration of sensory block and the duration of motor block were not significantly different in either groups. Complete motor block was achieved in all patients. CONCLUSIONS: Both 0.1% and 0.2% hypobaric tetracaine spinal anesthesia are suitable for a total hip replacement. However we got better results with 0.1% than with 0.2% tetracaine such as rapid and high sensory block with rapid motor block.